The setting affects the mood because the lab in the basement is kind of creepy and weird when you start out reading the book because it adds in a lot of mystery I think since Anna the main character doesn't know a lot about the lab, how long it has been there, why her dad didn't tell her about the lab. I think it also adds a lot of drama when she sneeks down in the lab because she doesn’t want to get caught by her dad for going down there without authorization from him or having Nick(one of the boys in the lab) tell her dad she went down in the lab.